Companies offering cloud storage facilities to UK customers are at the centre of a government review following complaints of price increases, service closures, and deleterious changes to terms and conditions.

Cloud storage is a great money-maker for many companies. The hip new name for "sticking your files on a remote server," companies from Microsoft and Google to telecommunications giant BT offer cloud storage services to businesses and consumers - and many attract new business with tempting offers such as discounted or free first-year subscriptions and the promise of 'unlimited' storage. Once the data is safely nestled on the servers, though, things change - and companies are accused of treating their customers as a captive audience, changing the rules and hoping that uploading all their data to a rival service is just too much hassle for their users.

In an official compliance review, spotted by Computer Weekly, the Competition and Markets Authority (CMA) is seeking answers to user complaints that accuse cloud storage companies of sudden and unexpected price increases, the removal of offers including unlimited storage, and even outright service closures without warning. The review seeks to investigate how widespread these issues are, and whether they may breach existing consumer protection law by misleading users about contract length, terms and conditions, or any limits that may apply.

The investigation comes after Microsoft cancelled its OneDrive unlimited storage offer following claims that a small number of users had been abusing the service, storing upwards of 75 terabytes of files on the service - 14,000 times that of the average user. As a result, Office 365 subscribers who had previously enjoyed unlimited OneDrive storage found their accounts limited to 1TB - but no refund or reduction in the subscription fee was offered.